Consider the following portion of mRNA produced by the normal order of DNA nucleotides:
5'ACA|UCA|CGG|GUA3'
c. Write the amino acid sequence if a mutation changes CGG to GGG. Is this likely to affect protein function?

Question

Consider the following portion of mRNA produced by the normal order of DNA nucleotides:

5'ACA|UCA|CGG|GUA3'

c. Write the amino acid sequence if a mutation changes CGG to GGG. Is this likely to affect protein function?

Accepted Answer

All right. Hello everyone. So this question is asking us to consider the given Mrna sequence. So we have from five prime to three prime Ggauu A AC C A provide the amino acid sequence resulting from a mutation that alters cua to UAA is the protein function affected by the mutation option A or excuse me, here we have four different answer choices labeled A through D proposing different sequences of amino acids and also whether or not the function of the protein is going to be effective. So here after I scroll down, you can see the MRN A sequences both before and after the mutation. So the nice thing is that this Mrna sequence, these MRN A sequences I should say have already been divided into codons, right, which are triplets of MRN A nucleotides that will code for one amino acid or one start or stop signal. So the mutation in question is really only affecting the last coda in the original MNA sequence. It's C A and in the mutated Mrna sequence, the final code on is UU A. So really the first nucleotide of this particular codon has been changed from C to U So in order to compare whether or not the function of the protein has changed because of the mutation, we have to come up with the amino acid sequences both before and after the mutation. By comparing these two protein, excuse me amino acid sequences, we can then compare if the change is drastic enough to affect the structure and therefore the function of the protein. So the good news is that you don't have to memorize the coons that will code for an amino acid, right? To do that, we can reference the genetic code table which is a table listing all of the possible code ons and what they represent or what they code for. So with our genetic code table, let's start with our original M RNA sequence. So our first code on is GG A which after referencing the genetic code table codes for glycine. So that's goy. Second code on is UC which codes for pheno alanine. So it's phe and then we have a AC which codes for asparagine. So that's a SN and the final code on of the original M RNA sequence C A codes for Lucy. So that's L eu so the original amino acid sequence is glycine, phenylalanine, asparagine and lucine. Now moving on to the mutated MNA sequence recall that only the last coon has been affected. So really the first three amino acids that is glycine, phenylalanine and asparagine are going to be the exact same. So now the question is what does this final code on after the mutation? Uu A code for? Well referencing our genetic table. It just so happens that UU A codes for lucine as well. So even after this mutation, the resulting code on still coded for the same amino acid, which means that the amino acid sequence is the exact same. So therefore, right, because no amino acid has changed after the mutation, the structure and therefore the function of the protein will not be affected. So there you have it. That means that our answer is going to be option d in the multiple choice. Because the amino acid sequence resulting from the mutation is glycine, pheno alanine, asparagine and lucine. And the protein function is not affected by the mutation because the amino acid sequence did not change. And so with that being said, thank you so very much for watching. And I hope you found this helpful.

Consider the following portion of mRNA produced by the normal order of DNA nucleotides:
5'ACA|UCA|CGG|GUA3'
c. Write the amino acid sequence if a mutation changes CGG to GGG. Is this likely to affect protein function?

Verified video answer for a similar problem:

Key Concepts

mRNA Translation

Amino Acid Codons

Mutation Impact on Protein Function

Consider the following portion of mRNA produced by the normal order of DNA nucleotides:5'ACA|UCA|CGG|GUA3'c. Write the amino acid sequence if a mutation changes CGG to GGG. Is this likely to affect protein function?

Verified video answer for a similar problem:

Key Concepts

mRNA Translation

Amino Acid Codons

Mutation Impact on Protein Function

Consider the following portion of mRNA produced by the normal order of DNA nucleotides:
5'ACA|UCA|CGG|GUA3'
c. Write the amino acid sequence if a mutation changes CGG to GGG. Is this likely to affect protein function?